By infrared sensors , remote control , GPS devices , the product is installed in the exhibition hall , when visitors enter the area , passing next to the device from the sensor to automatically start playing related audio commentary , but also through the remote control to choice or voice playback can be controlled by infrared sensors , remote controls , GPS devices , the product is installed in the exhibition hall , when visitors enter the area , passing next to the device from the sensor to automatically start playing related audio commentary , can also be selected by remote control or control voice playback.